The present invention relates to a disk system capable of storing a plurality of disks, for example CD's (compact disks), selecting a desired one of the disks, and processing the data stored in the selected disk.
A disk storage device, suitable for use in conjunction with the present invention is described in Applicants' co-pending U.S. patent application Ser. No. 08/103,355 filed concurrently herewith. In recent years, there has been developed and widely used a disk system including a storage portion, capable of storing a plurality of disks, and a processing portion for processing the data stored in a desired disk. The desired disk is selected by an operator and is then conveyed from the storage portion to the processing portion. Such systems are often utilized as CD players.
Systems of this type are generally equipped with a transfer portion for automatically transferring the selected disk from the storage portion to the processing portion where it is played. Systems including such transfer portions must have space, in the longitudinal direction, sufficient to array at least two disks transversely.
Since the CD has a diameter of 120 mm, for example, the space for the two disk array is 120 mm.times.2=240 mm. In the processing or player portion, moreover, a clearance has to be provided around the disk so that it may be allowed to turn. Since a clearance of 5 mm is provided between the inner wall of the system chassis and the disks in the storage portion, the minimum longitudinal size of the system chassis is 240 mm+5 mm .times.2=250 mm.
In recent years, therefore, in order to minimize the system size, there has been proposed a disk system wherein the disks stored in the storage portion and the disk set in the playing portion are partially overlapped. A disk system of this type is proposed in Japanese Patent Provisional Publication HEI2-260274 entitled "Disk Player".
Such a disk system is illustrated in FIGS. 23 to 27. Specifically, as shown in FIGS. 23A and 23B, a system chassis 1 having a rectangular box shape includes a storage portion 2, a transfer portion 3 and a player 4.
Storage portion 2 has a rectangular box shape and is formed in its righthand side with a plurality of slits 2a. Each of slits 2a receives a horizontal planar tray 2b. Tray 2b is equipped with a mechanism (not shown) for transferring its disk to player portion 4. The lefthand side of storage portion 2 is formed with rectangular slits 2c corresponding to trays 2b. Each of openings 2c is arcuately cut, as viewed from the top.
Transfer portion 3 includes a rod-shaped roller 3a and an upguide plate 3b, which extend in the longitudinal direction. Roller 3a, which is rotatable about a longitudinal axis, is positioned adjacent openings 2c of storage portion 2 and has a length greater than the diameter of disk 5. Upguide plate 3b, which has a length equal to that of roller 3a, is superposed thereover. Roller 3a and upguide plate 3b can be vertically displaced as shown in FIG. 27.
Player portion 4 includes a rectangular traverse plate 4a, a turntable 4b arranged over traverse plate 4a, and an optical pickup (not shown). Turntable 4b turns the disk while supporting it. The optical pickup reproduces the data stored in the disk. It is slidable along a straight line extending to the center of turntable 4b.
In the disk system thus constructed, disks 5 are stacked by inserting them one by one through individual slits 2a. Each of disks 5 thus stacked has an end portion exposed at the arcuate recesses formed by openings 2c. Roller 3a and upguide plate 3b of transfer portion 3 are vertically displaceable so that they can be moved to positions corresponding to individual openings 2c of storage portion 2 to select disks 5.
Thus, when a desired disk 5 is to be selected (at the disk selecting time), as shown in FIG. 24, player portion 4 and transfer portion 3 are adjusted to the height of the tray 2b storing the target disk 5, with roller 3a and upguide plate 3b of transfer portion 3 being closed. After disk 5 is extracted by an extraction mechanism (not shown), its edge is clamped by roller 3a and upguide plate 3b.
When selected disk 5 is to be transferred (at the disk transferring time), roller 3a is rotated. Then, disk 5 is extracted from storage portion 2 and transferred to player portion 4, where it is placed on turntable 4b.
When the data stored in transferred disk 5 is played (at the playing time), as shown in FIG. 25, roller 3a and upguide plate 3b are separated to release disk 5 and roller 3a moves away from disk 5 so that it does not obstruct rotation. As a result, disk 5 can be rotated on turntable 4b to perform the playing operation by the optical pickup. When disk 5 is returned to storage portion 2, roller 3a and upguide plate 3b are closed to clamp disk 5, which is slightly raised and moved toward storage portion 2 by rotating roller 3a in the direction opposite to that of the extraction.
In a disk system of the type described above, the distance between the center of turntable 4b and the center of disks 5 stacked in storage portion 2 is less than the disk diameter. As a result, a disk 5 in player portion 4 and disks 5 in storage portion 2 are partially overlapped. However, since the playing operation is carried out on a disk 5 which has been extracted from storage portion 2 without changing its vertical position, it does not interfere with the other disks 5 stacked in storage portion 2, but can be smoothly played. As a result, it is possible to increase the amount of overlap of the selected disk with those in storage, to reduce the size of the system.
When such a disk system is utilized as a CD player, for example, the individual components are of the following sizes. Specifically, if two disks 5 are partially overlapped, as shown in FIG. 26, the distance between the center of turntable 4b and the center of disks 5 stacked in storage portion 2 can be set to 93 mm. Since a typical CD has a radius of 60 mm, the distance between the center of disks 5 in storage portion 2 and the righthand side of system chassis 1 is 60 mm. Since a gap of 5 mm is necessary to avoid interference with the rotation of disk 5, the distance between the center of turntable 4b and the lefthand side of system chassis 1 is 65 mm. As a result, the longitudinal size of system chassis 1 is 93+60+65=218 mm, which is 38 mm shorter than the dimension of 250 mm of the earlier system.
The demand for miniaturized electronic devices has increased in recent years, including the demand for smaller disk systems. However, the ability to reduce the size of the aforementioned disk system by further shortening the distance between storage portion 2 and player portion 4 is limited.
At the disk selecting time, transfer portion 3 is displaced vertically, necessitating a horizontal gap to prevent interference between a disk 5 in transfer portion 3 and those in storage portion 2.
If, for example, the -distance between the center of turntable 4b and the center of disks 5 stacked in storage portion 2 is 93 mm, as in the aforementioned example of the CD player, transfer portion 3 is located 28.5 mm from the center of turntable 4b, as shown in FIG. 26. Considering that roller 3a and upguide plate 3b are opened and closed at the playing time, as shown in FIG. 27, 28.5 mm is the shortest distance between player portion 4 and transfer portion 3 allowing unimpeded disk rotation.
As a result, a minimum separation of the system components is required, especially at the disk selecting time and at the playing time, even if the system is to be miniaturized by overlapping two disks 5. Thus, the prior art approach cannot succeed in further reducing the distance separating system components.